Interpretive Summary: Costly sugarcane deterioration is increasing in Louisiana because if is now being harvested into shorter pieces than long stalks. Furthermore, the Louisiana sugarcane industry is under the threat of reducing or stopping all burning which means more sugarcane trash (leaves and tops) is being delivered at factories that detrimentally affects processing. This work presents a comprehensive review of several phases of work to better understand and monitor sugarcane deterioration by researchers and factory staff. This work will impact scientists, giving them a way to better confirm sugarcane deterioration, and also sugarcane farmers and factory processors by letting them know how to better harvest, handle and store cane, in order to reduce deterioration.

Technical Abstract:
Sugarcane deterioration in the field, factory storage pile, or during factory processing is a major technical concern, especially in those areas of the world where mechanical harvesting of billeted sugarcane has increased markedly. Sugarcane deterioration is complex and can be caused by adverse weather conditions including freezes and storms, and by excessive cut-to-crush delays. Harvest methods also have a stong effect on sugarcane deterioration, with more deterioration occuring in burnt versus non-burnt(green) sugarcane, and in mechanically harvested billeted sugarcane versus whole-stalk sugarcane. High performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), utilizing a 100mM NaOH/300 mM NaOAC in 100mM NaOH gradient has been used to simultaneously analyze for ethanol, mannitol and oligosaccharide (up to 12 degree of polymerization DP) sugarcane deterioration products in order to further understand and monitor the complexity of different types of sugarcane deterioration. Chemical, enzymatic, and microbial reactions are all involved in sugarcane deterioration and can cause the formation of oligosaccharides. The major oligosaccharides formed on sugarcane deterioration are: 1-,6- and neo-kestoses (GF2), nystose (GF3), and kestopentaose (GF4) isomers, as well as oligosaccharides formed as acceptor products from the action of dextransucrase in Leuconostoc bacterial strains, mainly isomaltotriose, isomaltotetraose, leucrose, and palatinose. Mannitol is also formed on sugarcane deterioration by Leuconostoc bacteria, and its rate of formation is higher than for oligosaccharides or ethanol and it is known to reduce sucrose recovery. Mannitol can also predict viscosity related processing problems equally as well, if not better than dextran. Laboratory and field studies have both shown that ethanol is not always a useful indicator of sugarcane deterioration.